Display panel having a plurality of display registers

ABSTRACT

A display panel includes a base plate carrying a plurality of slots in which anode electrodes are positioned. The slots are arrayed in groups with spacing slots exposed between the groups. Cathode electrodes are disposed on the surface of the base plate and operate with the anode electrodes to form scanning gas cells. Auxiliary anode and cathode electrodes are provided in selected spacing slots and are operated as keep-alive cells for the scanning cells.

United States Patent Inventors Gerald S. Rosenberg Edison; Robert E. Kollmyer, Middlesex, both of NJ. Appl. No. 26,504 Filed Apr. 8, 1970 Patented Dec. 7, 1971 Assignee Burroughs Corporation Detroit, Mich.

DISPLAY PANEL HAVING A PLURALITY 0F DISPLAY REGISTERS 3 Claims, 8 Drawing Figs.

US. Cl 313/220, 313/109.5, 313/210, 315/169 R lnt.Cl H0lj 17/16 Field of Search 315/169 R,

169 TV; 340/324 R; 313/1095, 220

O O O O O OO O O O O O O O OO O O O O O O O O OO O O [56] References Cited UNITED STATES PATENTS 2,925,530 2/1960 Engelbart 315/169 TV Primary ExaminerRaymond F. Hossfeld Allorneys-Kenneth L. Miller, Robert A. Green, George L.

Kensinger and Charles S. Hall ABSTRACT: A display panel includes a base plate carrying a plurality of slots in which anode electrodes are positioned. The slots are arrayed in groups with spacing slots exposed between the groups. Cathode electrodes are disposed on the surface of the base plate and operate with the anode electrodes to form scanning gas cells. Auxiliary anode and cathode electrodes are provided in selected spacing slots and are operated as keep-alive cells for the scanning cells.

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SUMMARY OF THE INVENTION Briefly, a display panel embodying the invention comprises a gas-filled envelope and an assembly therein including a plurality of gas-filled cells. The assembly includes a base plate which supports a plurality of groups of electrodes which control the operation of said cells, and auxiliary electrodes carried by said base plate and disposed between said groups of electrodes to serve as keep-alive electrodes for selected ones of said cells.

DESCRIPTION OF THE DRAWINGS FIG. I is a plan view of a panel embodying the invention and illustrating the capability thereof of displaying several registers of information;

FIG. 2 is a plan view of a portion of a display panel embodying the invention;

FIG. 3 is a perspective view of a portion of a panel embodying the invention showing a portion thereof which is associated with the portion shown in FIG. 2;

FIG. 4 is a sectional view along the lines 4-4 in FIG. 2 but including all other parts of the panel not shown in FIG. 2;

FIG. 5 is a sectional view along the lines 5-5 in FIG. 2 but including all other parts ofthe panel not shown in FIG. 2;

FIG. 6 is a section view along the lines 6-6 in FIG. 2 but including all other parts of the panel not shown in FIG. 2;

FIG. 7 is a sectional view along the lines 7 in FIG. 2 but including all other parts of the panel not shown in FIG. 2; and

FIG. 8 is a sectional view along the lines 8-8 in FIG. 2 but including all other parts ofthe panel not shown in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A display panel 10 described herein is a thin, flat, sheetlike member which may have substantially any desired size and shape from, for example, postage stamp size to wall size, and it may include substantially any number of display cells. The panel may also include any suitable ionizable gas such as neon, argon, xenon, etc., singly or in combination, with a vapor of a metal such as mercury usually included in the gas to minimize cathode sputtering. The panel, as illustrated in FIG. 1, displays three rows of characters, with each character being made up of a plurality of dots of light generated by gas-filled display cells and with a space being provided between each row of characters. Each row of characters is known as a register. Of course, the number of registers and the number of characters displayed per row may be readily increased in accordance with the principles described herein.

Ordinarily, display devices which use dots of light to form characters utilize a matrix of at least 7X7 dots to form a character. Such a matrix may also be used in panel 10 in actual practice. However, for purposes of illustration, a smaller number ofdots is shown and described.

The display panel I0, embodying the invention, includes a bottom plate of an hermetic, dielectric material, such glass or ceramic, which has a top surface 30, a bottom surface 40, an upper edge 50, a lower edge 60, a left edge 70, and a right edge 80. The plate 20 has a plurality of parallel slots or channels (A to N) formed in the top surface 30 thereof. For purposes of illustration, the panel is oriented so that the slots 90 extend horizontally across plate 20 from the left edge 70 to the right edge 80.

The array of slots 90 is suitably positioned between the upper and lower edges of plate 20, with the first slot 90A being closest to the upper edge 50 of the plate, and the last slot 90N being closest to the lower edge 60 of the plate.

The slots 90 are all identical in size, shape, width, depth, etc., and can be made by any suitable mass production process. For purposes of illustration, three slots 90 are used in forming a row or register of characters I2, in a manner to be described, and the plate includesthree groups of three slots 90 for displaying three rows of characters: with, say two, nondisplay slots 90 between each group of three display slots. The two nondisplay slots provide spacing between each row of characters.

In panel I0, slots 90A, B, C form one display register; slots 90D and E form nondisplay, interregister slots; slots 90F, G, H form the next display register; slots 90] and K form the next nondisplay, interregister slots; and slots 90L, M, N form the third display register.

Electrodes 110, which are used as counting or scanning anodes in one mode of operation of the panel, are seated in each of the three display slots 90 of each character display register, and these electrodes extend beyond the left and right edges of plate 20 and of the panel 10 so that they are accessible outside the panel. Electrode are preferably individual wires set into the slots; however, they may also be plated, evaporated, or otherwise formed in the slots. The electrodes 110, if separate wires mightalso be secured in the slots 90 by means of a cement such as a fused glass frit or the like.

According to the invention, an auxiliary wire electrode is seated in slot 90D, auxiliary wire electrode 121 is seated in slot 90E, auxiliary wire electrode I23 is seated in slot 901, and auxiliary wire electrode is seated in slot 90K. These wires are short, and they extend only a short distance into plate 20 from the left edge thereof, and they are held in place by means of an insulating material 93, such as a glass frit, to which their inner ends are secured. The inner ends' of the wires do not extend into the panel as far as electrode I61 described below. A transverse slot 113 is provided in plate 20 between slots 90D and.90E, and a similar slot 115 is provided between slots 90] and 90K. These slots permit electrodes I20 and 121 and electrodes I23 and 125 to operate with each other. Under some circumstances, there may be sufficient spacing between the adjacent surfaces of the bottom and center plates to provide the desired communication between electrodes I20 and I2] and between electrodes I23 and 125.

Plate 10 also includes a center sheet or plate I30 of a dielectric material, the same as the material of plate 20 if desired, which is seated on bottom plate 20 and has a top surface 132 and a bottom surface 134. The plate is provided with a plurality of rows and columns of holes: 144, and the bottom surface 134 thereof is provided with a plurality of generally rectangular, parallel, vertical slots 150 A to N. Slots 150 all have the same width and depth and extend along sheet I30 from the lower edge 138 to the upper edge 136. The slots I50 are oriented at 90 to each of the slots 90, and thus, in in effect, cross each of the slots 90 in the bottom plate 20. The array of slots 150 is suitably positioned between the left and right edges I40 and 142, respectively, of center sheet I30, with the first slot 150A (FIG. 3) considered to be the first slot positioned near the left edge 140 of sheet 130, and the last slot I50N being positioned close to the right edge 142 of sheet I30.

In plate 130, the holes 144 are arrayed in rows and columns, with the columns of holes aligned with and overlying each of slots 1508 to I50N but not slot A. The rows of holes I44 are generally aligned with and overlie all of the slots 90. The holes I44 are all identical, and the slots I50 are all identical, and each may be made by any suitable mass production process. I-Ioles 144 are not required over the interregister, nondisplay slots 90. However, in mass production manufacture of the plate 130, it is as easy to provide them as not.

A plurality of electrodes 160A to M, operated as scanning cathodes, are seated in the slots 150B to N, respectively, in sheet 130. The scanning cathode electrodes 160 are metal strips which substantially fill the slots 150 and extend along the entire length thereof and beyond the upper and lower edges of plate 130. The cathodes 160 are oriented at 90 to the anodes l 10, and each cathode crosses each anode. Each electrode 160 is provided with a plurality of tiny apertures 162 disposed along its length, with each aperture 162 being generally centrally positioned over a slot 90 (FIG. 4) in bottom plate 20 and beneath a hole 144 in center plate 130. Each column of cathode apertures 162 is aligned with a column of holes 144, and the rows of apertures 162 formed by the adjacent cathodes are aligned with the rows of holes 144. Apertures 162 are not required over interregister slots 90. The cathodes 160 are identical in size and shape and can be made by any suitable mass production process.

An unapertured cathode strip electrode 161, which is somewhat narrower than the cathodes 160 and the slots 150, is seated in slot 150A. The cathode electrode 160 and electrode 16] need not be seated in slots in plate 130, if desired; they may be merely positioned between the adjacent surfaces of the bottom and center plates, with the center plate being unslotted.

A second group of wire electrodes 180, used as display anodes, are seated on or in the top surface 132 of plate 130, one for each wire electrode 110 in plate 90. Each electrode 180 is parallel to and aligned with an electrode 110. Each electrode 180 is generally aligned with and overlays a row of holes 144 in center sheet 130. The electrodes 180 need not be centered over the holes; they need only communicate with the gas in the holes. Thus positioned, electrodes 180 are parallel to and are aligned with wire electrodes 1 in plate 20.

A transparent cover or viewing plate 190 of a dielectric material such as glass completes the panel and is seated on center plate 130. The wire electrodes 180 might be seated in slots in the bottom surface of top plate 190, as shown in FIGS. 6 to 8, if desired. In the completed panel 10, the three plates 20, 130, and 190 are hermetically secured together by a seal 200 formed along their adjacent edges by any suitable means such as a fused glass frit (Pyroceram) or the like.

The gas used in panel 10 is introduced in any suitable manner, for example, by means of a tubulation 203 (shown only in FIG. 4), secured to bottom plate 20.

As described, panel 10 includes, in each register, a lower layer of gas cells 210 which are called counting or scanning cells (FIGS. 2, 4, and 8) arrayed in rows and columns, with each cell comprising a portion of an apertured strip cathode electrode 160 a portion of an anode 110, and the gas volume between these electrodes in slot 90. Thus, each column of counting cells is defined by each cathode 160 and its crossing of a slot 90 and the associated portion of a counting anode 110. As seen in FIG. 2, there are twelve columns of counting or scanning cells 210, and, for purposes of description, the first column is associated with cathode 160A, the second column with cathode 1608, the third column with cathode 160C, etc. Each column of scanning cells 210 communicates with the adjacent column, that is, each scanning cell in one column communicates with the corresponding cell in the adjacent column, through the associated slot 90.

The panel 10 also includes an upper layer of gas cells 220, known as display cells, associated with the positioned above and generally aligned with, the counting cells 210. Each display cell 220 (FIGS. 4, 5, and 8) is made up ofa portion ofa cathode 160, the associated gas-filled hole or cell 144 in center sheet 130, and the associated portion of upper anode electrode 180. As with the counting cells, there are also twelve columns of display column cells 220, each associated with a cathode 160, with the first column associated with cathode 160A, etc.

The panel 10 also includes a column of auxiliary cells 224, which are known variously as starter cells, reset cells, particlesupply cells, or glow-spreading cells (FIGS. 2 and 7), and these cells supply excited particles to facilitate the turn-on of the first column of counting cells 210 associated with cathode 160A at the beginning of a scanning cycle, to be described. For convenience, cells 224 will be called reset cells. These reset cells are arrayed in a column to the left of the first column of counting cells an communicating therewith through slots A, B, C, and F, G, H, and L, M, N. Cells 224 are constituted by the cathode strip 161 and the portion of each anode which it crosses and the gas volume in the slots 90 therebetween.

Generally, in operation of a display panel such as panel 10, particularly in a scanning type of operation (see Ser. No. 850,984, filed Aug. 18, 1969) wherein the columns of scanning cells are fired in turn and in series beginning at the left end of the panel and proceeding to the right end thereof, it is customary to provide the reset cells 224 to facilitate the turn-on of the first column of scanning cells which are associated with display cells. Other arrangements are known for providing and operating such starter cells (see Ser. No. 881,024, filed Dec. 1, 1969). In addition, it is desirable to provide auxiliary cells, known as keep-alive cells, for operation of the starter cells.

In a keep-alive arrangement according to the invention and referring to panel 10, the electrodes 120, 121 and 123, in the interregister slots 90 are used, one in each pair as an anode and one in each pair as a cathode to provide a keep-alive function. The two keep-alive cells 228 formed by these pairs of electrodes communicate with the associated reset cells through spaces in and around the masses 93 and thereby provide excited particles to facilitate the operation of the reset cells.

The keep-alive function of cells 228 is achieved by having the keep-alive cells always ON and fired, by the application of suitable positive and negative potentials, to maintain a constant supply of excited particles for the reset cells.

As noted above, the keep-alive electrodes 120, 121, 123 and 125 are terminated short of the reset cathode 161 but within operating distance thereof. Thus these electrodes are relatively remote from the other cathodes and from the anodes 110. With the electrodes thus positioned and with insulating masses 93 disposed within the slots 90 in which they are located, the keep-alive electrodes are in operative relation with the reset cathode 161 and do not affect the operation of the other anodes and cathodes. Those skilled in the art will appreciate that this is the desired mode of operation of the keepalive electrodes. As noted, the excited particles provided by the keep-alive cells 228, including electrons, ions and the like, reach the reset cathode through spaces in and around the insulating material 93. Even if these masses of insulating material appear to the eye to fill the slots 90, the microscopic excited particles can penetrate to reach the reset cathode through minute openings in the contact area between the insulating material and the slot 90.

In the description of the operation of the invention set forth below, reference is made to scanning or glow transfer from cell to cell or column to column. Several different types of actions occur including glow transfer from the keep-alive cells 228 to the reset cells 224, from the reset cells 224 to the scanning or counting cells 210, from a scanning cell to a scanning cell, and from a scanning cell to a display cell 220. The exact mechanism by which each such operation occurs is not known for certain; however, the operations may involve actual transfer of a mass of glowing ionized gas, or the diffusion of excited particles including metastable states which facilitate a new firing of an OFF cell, or both mechanisms may be involved.

In operation of the panel 10, the keep-alive cells 228 communicate with the reset cells 224 through slots 90D and E and slots 90J and K. When it is desired to turn on the reset cells 224, operating potential is applied to the reset cathode 161 and to all of the anodes 110. With the aid of excited particles from the keep-alive cells, glow spreads along the entire length of the reset cathode 161 in thespaces 170 (FIG. 4) on either side thereof.

When the reset cells 224 have fired, the first column of counting cells 210 can be fired with the aid of excited particles generated in the reset cells and able to diffuse to the first column of counting cells through slots 90A, B, C and 90F, G, H and 90L, M, N. An arrangement for using reset cells to fire counting cells is described and claimed in copending application Ser. No. 791,208. In addition, methods and apparatus including circuits for scanning columns of counting cells and energizing display cells therefrom are described and claimed in the above-mentioned application Ser. No. 850,984. These circuits are not shown here. In a typical scanning operation, the scanning or counting anodes 110 are connected to driver circuits for applying generally positive operating potential thereto, and each of the cathodes 160 is connected to a driver circuit for applying generally negative operating potential to each, sequentially, to cause each column of counting cells 210 to fire and glow. The firing of each column of counting cells, after the first has been fired, is facilitated by the diffusion of excited particles through the slots 90 from ON counting cells to the adjacent OFF counting cells to be fired. The columns of counting cells 210 are fired sequentially from left to right, as seen in FIG. 2. This sequential firing of the columns of lower counting cells 210 is carried out cyclically from left to right. Each time the last column of counting cells at the right-hand edge of the panel is reached, the column of reset cells 224 at the left-hand edge of the panel is turned on again, with the aid of the keep-alive cells, and the above-described cycle is repeated. If desired, circuit means may be provided to sense the turn-on of the last column of counting cells 120 and automatically turn on the reset cells to start the cycle again.

When it is desired to fire cells 220 in the upper layer to provide a display of information or the like, generally positive operating potentials are applied to the proper upper anodes 180 associated with the cells 220 to be fired and glow transfers from the associated lower cells 210 through the aperturesl62 in cathode electrodes 160 to the upper cells where the glow can be viewed through top plate 190. As described above, the glow transfer is facilitated by the presence of excited particles in each of the lower counting cells 210 when it is fired. By properly synchronizing the switching of the cathodes with the application of information signals to the display anodes 180, the desired characters are displayed in each register.

It is clear that modifications may be made in the panels described within the scope of the invention. For example, although the panel as described is scanned from left to right, the scanning may be effected in other ways, and this might require a rearrangement of parts. In addition, in some modes of operation, keep-alive cells may not be required, and, in some cases, both keep-alive cells and reset cells may not be needed.

In general, the drawings are not intended to be dimensionally exact, and, in a typical display panel embodying the invention, the top plate 190 and bottom plate are about one-fourth inch in thickness, and the center plate 130 is about 40 mils in thickness. In addition, in plates 20, slots 90 are 10 mils wide and mils deep, and electrodes 110 and 120 are 5 mils in diameter. In plate 130, slots 150 are 36 mils wide and l to 3 mils deep, with cathodes 167, 160 A to M having approximately the same dimensions. The holes 162 in the cathodes are 1 to 3 mils in diameter, the holes 144 in plate 130 are 18 to 24 mils in diameter and mils deep, and electrodes 180 are about 3 mils in diameter.

It is to be understood that the copending applications mentioned above are incorporated herein by reference.

In illustrating the principles of the invention, specific panel structures have been described. However, it will be clear to those skilled in the art that modifications may be made in the specific features shown and described. For example, the sizes and shapes of the various parts may be modified and suitable materials therefore may be readily selected. In addition, the panel as described may be sealed inside an envelope so that, with respect to the panel itself, .only a mechanical coupling of the various plates and electrodes would be required, and the seal around the edges of the panel could be omitted.

We claim:

1. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material,

said bottom plate having a top surface and a bottom surface,

said bottom plate also having a plurality of first parallel identical slots extending into said plate from said top surface and extending along the entire length of said plate,

first electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of first slots comprising display register,

each of said several groups of said first slots being separated by an interregister space,

a pair of second electrodes seated in each of said interregister spaces in communication with each other and comprising a source of excited particles,

said center plate having a top surface and a bottom surface,

a plurality of third electrodes disposed between said bottom plate and said center plate and oriented at an angle to said first electrodes, each third electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the crossing,

a fourth electrode disposed between said bottom plate and said center plate and positioned closer to each said second electrode than each said third electrode,

a plurality of holes formed in said center plate and arrayed in rows and columns, each column. of holes being aligned with one of said third electrodes, and

a plurality of fifth electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each fifth electrode also being aligned with one of saidfirst electrodes,

said first electrodes being adapted to be operated as anodes with respect to said third electrodes operated as cathodes, said fourth electrode being adapted to be operated as a cathode with respect to said first electrodes being operated as anodes.

2. A display panel comprising a gasfilled envelope including a bottom plate, a center plate, and a top plate, all being ofdielectric material,

said bottom plate having a top surface and a bottom surface,

said bottom plate also having a plurality of first parallel slots extending into said plate from said top surface and extending along the entire length of said plate,

first anode electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of slots being associated with display, registers,

each of said several groups of said first'slots being separated by an interregister space which contains a pair of second electrodes,

said center plate having a top surfaceand a bottom surface,

a plurality of cathode electrodes disposed between said bottorn plate and said center plate and oriented at to said first electrodes, each cathode electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes'at the cell crossing,

said cathode electrodes being disposed in an array including a first and a last cathode,

a first auxiliary cathode electrode adjacent to the first cathode in said array of cathode electrodes and positioned in operative relation with said first anode electrodes,

each said pair of second electrodes being adjacent to said first auxiliary electrode and adapted to provide excited particles therefor,

7 8 in each said pair of second electrodes, one electrode being a plurality of third anode electrodes aligned with the rows of adapted to be operated as an anode and one as a cathode, said holes and disposed between said top plate and said said pairs of second electrodes being adapted to be maincenter plate, each third electrode also being aligned with tained in the tired state continually to provide a constant One of Sald first electrodessource of excited particles for said first auxiliary elec- The Panel defined i claim 2 wherein each Said Cathode electrode comprises a metal strip which has a series of apertures extending along its length, each said aperture communicating with a hole in said center plate.

trode, a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said cathode electrodes, and I0 

1. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material, said bottom plate having a top surface and a bottom surface, said bottom plate also having a plurality of first parallel identical slots extending into said plate from said top surface and extending along the entire length of said plate, first electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of first slots comprising display registers, each of said several groups of said first slots being separated by an interregister space, a pair of second electrodes seated in each of said interregister spaces in communication with each other and comprising a source of excited particles, said center plate having a top surface and a bottom surface, a plurality of third electrodes disposed between said bottom plate and said center plate and oriented at an angle to said first electrodes, each third electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the crossing, a fourth electrode disposed between said bottom plate and said center plate and positiOned closer to each said second electrode than each said third electrode, a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said third electrodes, and a plurality of fifth electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each fifth electrode also being aligned with one of said first electrodes, said first electrodes being adapted to be operated as anodes with respect to said third electrodes operated as cathodes, said fourth electrode being adapted to be operated as a cathode with respect to said first electrodes being operated as anodes.
 2. A display panel comprising a gas-filled envelope including a bottom plate, a center plate, and a top plate, all being of dielectric material, said bottom plate having a top surface and a bottom surface, said bottom plate also having a plurality of first parallel slots extending into said plate from said top surface and extending along the entire length of said plate, first anode electrodes seated in several groups of said first slots and extending along the entire length thereof and beyond both ends thereof, said groups of slots being associated with display registers, each of said several groups of said first slots being separated by an interregister space which contains a pair of second electrodes, said center plate having a top surface and a bottom surface, a plurality of cathode electrodes disposed between said bottom plate and said center plate and oriented at 90* to said first electrodes, each cathode electrode crossing each first electrode, each crossing defining a cell which can be fired by potentials applied to the two electrodes at the cell crossing, said cathode electrodes being disposed in an array including a first and a last cathode, a first auxiliary cathode electrode adjacent to the first cathode in said array of cathode electrodes and positioned in operative relation with said first anode electrodes, each said pair of second electrodes being adjacent to said first auxiliary electrode and adapted to provide excited particles therefor, in each said pair of second electrodes, one electrode being adapted to be operated as an anode and one as a cathode, said pairs of second electrodes being adapted to be maintained in the fired state continually to provide a constant source of excited particles for said first auxiliary electrode, a plurality of holes formed in said center plate and arrayed in rows and columns, each column of holes being aligned with one of said cathode electrodes, and a plurality of third anode electrodes aligned with the rows of said holes and disposed between said top plate and said center plate, each third electrode also being aligned with one of said first electrodes.
 3. The panel defined in claim 2 wherein each said cathode electrode comprises a metal strip which has a series of apertures extending along its length, each said aperture communicating with a hole in said center plate. 